PORT TOWNSEND — Discovery Bay has been closed to all recreational harvest of shellfish after marine biotoxins that cause Paralytic Shellfish Poisoning, or PSP, were detected at high concentrations in samples, the Jefferson County Public Health Department said.

The state Department of Health closed the beaches, said Michael Dawson, lead environmental health specialist for the county.

Commercially harvested shellfish are tested for toxin prior to distribution and should be safe to eat.Warnings posted

Warning signs have been posted at high-use beaches warning people not to consume shellfish from these areas.

The closure includes clams, oysters, mussels, scallops and other species of molluscan shellfish. This closure does not apply to shrimp.

Crab meat is not known to contain the biotoxin but the guts can contain unsafe levels. To be safe, clean crab thoroughly and discard the guts.

The closure announced Monday is in addtion to prior closures of the Port Ludlow area, including Mats Mats Bay, and Kilisut Harbor, including Mystery Bay, to the harvest of butter and varnish clams only.

In Clallam County, Dungeness Bay is open for recreational harvest of shellfish, while Sequim Bay and the Strait of Juan de Fuca from Pillar Point west to Cape Flattery is closed for shellfish harvesting.

Ocean beaches are closed to the recreational harvest of all species of shellfish from April 1 to Oct. 31 each year. Marine biotoxins are not destroyed by cooking or freezing.

Symptoms of PSP can appear within minutes or hours and usually begins with tingling lips and tongue, moving to the hands and feet, followed by difficulty breathing, and potentially death. Anyone experiencing these symptoms should contact a health care provider immediately. For extreme reactions call 9-1-1.